This week Amazon made a big change to their Marketplace email system. They’ve strengthened the email opt-out system for Amazon customers -- arguably a good thing for the customer -- and correspondingly weakened the ability of sellers to reliably reach customers with support information or feedback-related messages.
The new system works by allowing Amazon customers to opt-out of all emails from all Amazon sellers with one setting. Emails from sellers appear to be sent successfully, but trigger the following bounce notification.

What does this mean for anyone using Email Automation tools?

Messages sent to opted-out accounts will simply not be delivered to those buyers. This will also trigger bounce notifications to the primary seller seller account email address from auto-communication@amazon.com.

Can sellers connect with buyers who opted out?

Our interpretation about this change is that sellers can still connect with opted-out buyers as long as the message is critical to the completion of the order. How does that work? In the undelivered message email above Amazon has outlined an override option via buyer-seller messaging on seller central. This is the "Additional Information Required" override for critical information. As sellers, you would need to be careful not to include non-critical elements in those “critical” messages. Certainly no review requests.

Does this imply that sellers should not be asking for reviews in follow-up emails?

No, we do not believe that to be the case. As long as you’re not using the "Additional Information Required" override, emails can go out for every order. The emails can include asking for reviews. They will be delivered to customers who haven’t opted out. As always, you have to be careful to follow Amazon’s overall email and review solicitation guidelines.

What percent of emails are affected?

Currently, we’re seeing 1.3% of emails to customers affected based on a sample of a few thousand emails from a single seller -- a very small number so far. This may reflect the actual number of customer opt-outs at this point, or just Amazon doing a phased roll-out. In any case, the percentage is certain to go up over time. One could guess it will probably top out in the low double digits, as that might match norms for customer opt-outs for order related information.

Conclusion

As always, buyer-seller messaging needs to be related to a specific order. But now Amazon is dividing the possible things you might email about into two categories: “critical” and “non-critical”. Your non-critical emails may not be delivered if the customer has opted out from seller emails. Your “critical” emails will be delivered if you use their new special mechanism, but you have to be careful to only include approved content (Product customization questions, Delivery scheduling, Issues with a shipping address).

Is this good for customers? Yes, more control over email volume is good.

Is this bad for sellers? It’s a challenge. But customers who opt out of seller messaging were not likely to leave you a review anyway. As long as you are doing the right thing for the customer, this change is like one of many changes that Amazon has introduced over time to improve their obsessive commitment to customer satisfaction.